Good Sales and Purchase software integrating to Tally

Hi,

As part of my final year research, I'm analyzing on ERP Tools for SMB segment in India. I have even seen Tally ERP 9 and my survey findings revealed that Tally users are very  happy with Accounts module and not so with sales, purchase and other modules.

Is there any good software in the market that works with Tally for Accounting and gives good sales, purchase and other modules.

Thanks in advance

Nikita